Unit 3 Flashcards
Halogens
What do Halogens form when they react with metals?
Salts
Can all halogens exist as diatomic molecules?
Yes they can covalently bond with each other
Are halogens metals?
No, so they cant conduct electricity
Are halogens good oxidising agents or reducing agents
Oxidising agents, Remove electrons form other species have large electron affinity
What happens to the melting/B points as you go down the halogen group?
They increase due to increased mass. More van der waals forces
What property do bromine and iodine have?
They are both volatile ( low boiling point, vaporize easily). All halogens are volatile its just bromine and iodine are solids, the rest are gasses naturally
Iodine goes through a process of sublimation, what does this mean?
When heated it goes straight from a solid to a gas
Why does reactivity decrease down the halogen group?
Because the further down you go means more energy levels (shells) which means it is harder to attract another electron
What is a displacement reaction?
When an element replaces another in the reaction if it is more reactive. So a metal can replace another metal in a metal oxide if it is more reactive and make its own oxide
What does fluorine do to water?
Oxidises it so that it forms oxygen and ozone
What do chlorine and bromine do to water?
They make it an acidic solution
What does iodine do in water?
It is insoluble, but can be dissolved if there are other iodide ions
How do all of the halogens react with hydrogen?
They form covalent bonds.
Fluorine will explode with H
Chlorine will produce chloride gas if there is a flame
bromine will give hydrogen bromide gas
Iodine will only partially combine. an equilibrium is set up
Why does HF have a really high boiling point?
There’s H-bonding
Which halogens are strong acids and why?
All except HF are strong acids as they easily donate a proton.
